Abstract: Deep charging effect caused by high-energy electron irradiation is one of the key factors threatening spacecraft safety under the environment of space radiation. This paper compares the deep charging progress of different thickness polyimide films under different electron beam intensity, simulates the GEO orbit radiation environment with Sr90 radioactive source, and studies the charging progress of Delrin and Teflon under its radiation. This paper also presents a new model, which simulate the experiment results. It also analyzes the deep charging equilibrium potential and time with different electron intensity and dielectrics resistance. It shows that deep charging effect becomes more serious with increasing electron beam intensity and dielectrics resistance, and the time to reach charging equilibrium is mainly affected by dielectrics resistance.